It is strongly required to reduce a power consumption of a radio communication apparatus. If, in order to reduce the power consumption of waiting time, the radio communication apparatus is activated only when communicating, there is a problem that activating and setting the radio communication apparatus bothers users. Therefore, one idea is to perform intermittent operation to realize both low power consumption and convenience. However, the intermittent operation may make the time to start the communication longer, which may cause communication trouble.